Clinicopatholgical correlates of long COVID and potential interventions for improving the quality of life

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the third coronavirus to jump species to humans in the past 10 years and is the causative agent for COVID-19. While the mortality rate is the lowest for SARS-CoV-2 when compared to SARS-CoV and MERS- CoV, its high infectivity has made it cause the worst pandemic in the past 100 years after the Spanish flu. Majority of COVID-19 infections are asymptomic and relatively mild, with recovery typically within 2-3weeks, but 1-3% of infected individuals develop severe illness, which is postulated to be related to both an overactive immune response and viral-induced pathology. Unknown proportion of all the infected individuals after recovering from the initial illness, develop a so-called "long COVID," in which they experience persistent symptoms not necessarily related to the infection directly. The syndrome appears to affect those with mild as well as moderate-to-severe disease. The incidence, natural history and etiology of these symptoms is currently unknown. It is not know whether long-Covid-19 is observed only in individuals with primary infections, or it can also develop in vaccinated individuals who are infected. In this study we will address the characteristics of the immune responses in infected- recovered individuals who experience or not long Covid-19 and in vaccinated individuals. These studies will pave way for future programs that target Covid-19.